loubikes

I opened up a front hub (Shimano 105) on an old Bianchi Brava and it has 11 bearings on both sides. I started reading about bearings and folks were saying there should be some free space (about the width of a ball/bearing) and I don't have any extra space in mine.

I looked up an exploded view of Shimano 105 (1050 is on the dust cap, and I found a doc with that on it and I'm assuming the F on the docs stands for 'front'). I found it here.

In the exploded view, it shows 10 bearings. I just hesitate, because I find it hard to believe that the wrong number had been put in.

MY QUESTION: Is it possible that the I have found the wrong diagram for my hub? It's pretty old. Can anyone say with a high degree of confidence how many it should be? I don't have any real experience with hubs.

Thanks!

fietsbob

(Old School, hands on, pre internet) 1) get the right size balls .. measure the originals.

the bearing fill will be just the number that go around the cup race with out pushing one out, that extra is one too many then.

Then you don't have to count them out...






.....

blamester

Leave a gap. Fill it up completely and remove one.
I always thought it was 10 but i would have to go and look.

SquidPuppet

Not likely. It clearly says 105 FRONT.


If there is no gap, there are too many balls.

So, since the diagram calls for ten, and eleven leaves no gap, I have a high degree of confidence in recommending ten.

A previous owner/mechanic was probably unaware and just stuffed it full. An understandable error.

loubikes

That's what initially gave me pause, I found other, "105 Front" diagrams that have 11 bearings but they don't look like my hub and then I found "1050" on the dust cap, which I guess is some sort of model number.

Thanks for the reply, I'm feeling confident about 10 now.

SquidPuppet

Yep, there are exceptions. Dura-Ace track hubs take eleven too. But, the rule of thumb is "Full minus one". Or, "One too few is always better than one too many."

kcblair

I have Shimano 600 hubs on most my bikes and various hubs on other bikes. They all take 10 x 2 , 3/16 loose balls. KB

pesty

I couldn’t speak to older hubs, but I have rebuilt several Shimano Ultegra and 105 hubs series 5500/6500 and newer, and never did one of them have a gap when I removed the cone. The only time I’ve seen gaps are when there are retainers/spacers.

blamester

There is a small gap between each ball bearing or they would rub on each other and not roll.
1 big gap upon assembly turns into many small ones when the cone and bearings are properly seated.

pesty

I’m not following you. Yes, there will be tiny gaps between the balls, but with the balls fully pushed back against the outer race, that gap is fractions of a mm on the 9s and newer hubs. Certainally not enough combined gap big enough to fit a full ball.

Retro Grouch 

I honestly don't know the correct number but I'm an analogue guy so here's what I do:

If 11 looks right, take one out. Better one too few than one too many. It's important that the balls don't rub one another in use.

cny-bikeman

No, that's the point. It's not typically enough for a full ball, but it can be close enough that people have put too many in and reassembled. When a hub is disassembled the balls may be distributed evenly enough that the extra space is not noticeable. Even if there is almost room for another ball the space between each would average on the order of .01" or .4mm.

pesty

Ok, maybe I'm just missing something. When I put back in the balls I make sure they are all touching the outer race before I re-assemble. Grease typically holds them in place well enough and there is never enough room for an extra ball. If the balls aren't touching the outer race, I could see how it would look like there's an extra ball until they are fully seated.

When I see comments like "If 11 looks right, take one out. Better one too few than one too many." it concerns me as this causes uneven loads on the races and balls and can lead to premature wear. You should not physically be able to install the cone if you have "too many" balls unless you have the wrong size balls. I just don't want us giving the OP bad or confusing information and then they have to go try and find and replace pitted cones before they should really have to.

HillRider

Older Shimano front hubs required 10x3/16" bearing balls per side but many of their newer hubs take 11. The 1050 hub the OP describes is from the 8-speed 105 group and most likely requires 10 per side.

Edit: I just looked up the HB-1050F exploded view in Shimano's Dealer-User manual web site and it does indeed show 10x 3/16" balls per side.

cny-bikeman

I would agree that the "If 11 looks right..." comment is perhaps not specific enough. If 11 balls can fit and there is any room left, then 11 would appear to be the right amount. However, I disagree that "You should not physically be able to install the cone if you have "too many" balls," because I have seen in done with the correct size, and there have been posts on this forum as well where people have done so.

davidad

I've piddled around with shmano hubs and until lately the fronts took 10 3/16" per side and the freehubs took 9 1/4" per side.

sweeks

This is exactly my experience with a set of Ultegra hubs (2001 vintage) and another set of low-end Shimano hubs of similar vintage.
Steve

FBinNY 

General answer, so you'll always know, regardless of the specific bearing.

2 rules apply.

1- there must be a gap such that the balls can spread out and not rub each other. Typically in bike bearings, the gap will be something less than one ball if all the balls are pushed together on one side. So far, I've never seen one where you could pack it full with only tiny or no gap. It's obvious when it's overloaded because the balls cannot lie a circle at the same height. You'll either have obvious friction before the play is removed, or the axle will be pushed to one side by the high ball, and wobble as you spin it. So the high limit isn't hard to find.

2- the maximum gap cannot be excessive. Seven balls (with spacers) is very common in commercial bearings, and some are made with only six. So, even when spaced, there's be a gap spanning 60° of arc in normal use, and obviously, that's not a problem. So, consider an gap of 60° if all the balls are pushed together as the max. On a bearing made for 9 balls or so, that would be greater than 1-1/2 balls. So, one short won't be an issue.

There you have it, pack the bearing full (maybe too full) then remove one ball. Or pack it leaving a gap of something close to one ball's width. Then push the cone against the packed cup and turn it a bit to put the balls into the actual circle where they live, then remove and eyeball before final assembly.

In any case 9 in a bearing that might 10 won't be an issue.

Al Criner

Fun Fact: 105 5501 series uses 11 balls in the front hub. You can confirm this with the exploded view. This might be the only one.

HillRider

Not the only one. The front hub of Shimano's WH-R560 wheel set also uses 11x3/16" balls per side.

grizzly59

Scratching my head,

https://wheelsmfg.com/tech/PDF/hub/hb-5501.pdf

Item 9 in list, 20 balls- 10 per side. Now count them in the drawing- 11 per side.

Look at the attached PDF- Item 9 is for 20 balls, now the drawing has 10 per side.

The drawing looks like a Shimano drawing, you can read the model on the hub.

mikezs

I know this is an old thread, but I've just stumbled across this issue on a hub that is damaged from what I suspected to be too many bearings (11 per side) but when I looked at the Shimano document for the hub, it specifies 22 BB's for the hub total.

There's barely any space between the balls, but I assume because it's a disk hub it might need the one extra?



Another point to note is there same hub HB-M495 (without the A designation), which is also disc, specifies 10 per side. So i'm thoroughly confused.

I am going to follow Shimano's original specs on this one, and put 11 per side back in now I've sanded a new race in the cone, but just thought this was mildly interesting.

Narks

Interestingly, Shimano 5500 diagrams show 10 balls per side whilst 5501 shows 11 per side! Same series, virtually identical hubs yet different specs!

I put 11 per side in my 5500, there’s ample room, works fine! I agree with other comments, overfilling would be obvious, axle would not align correctlly if balks are not seating properly, so long as there’s any, even minor space between balls, should be ok